1. introduction the position of iran in the subtropical region that has made its arid and semiarid climate and the topographic diversity changes this trend of climate. therefore, climate hazards such as frost, flood, dust storm, drought, temperature anomalies, heavy rainfall, avalanches, snow, sleet, etc occur in iran. the northwest of iran experiences the above conditions following the arrival...

introduction zayanderood basin is one of the major internal river basins in the central iran, where zayanderood river is the only permanent river. fluctuations in rainfall in recent years have affected different areas of iran. because of the dependence of the provinces of isfahan, yazd, and kerman on water resources of this basin, changes and fluctuations in precipitation within this watershed ...

The Black Sea is the largest anoxic basin on earth and provides unique conditions for the study of microbial habitats and controls on key anaerobic microbial processes in the element cycles. Recent studies of European research programs carried out in situ measurements of fluxes and turnover of methane and sulfur at seep systems of the Black Sea, and investigated the microbial diversity in perma...

introductionmany aspect strongly influence regional climate includes localized surface processes, large-scale patterns, especially mid and upper level tropospheric circulation and many factors control precipitation in the west of iran includes location of emigrate westerly winds systems, jet streams location, humidity flux and topography. upper tropospheric jet stream constitutes a significant ...

1. introduction heavy snow hazards, although have less frequency in comparison with extreme weather events such as freezing, but are major hazards in midlatitudes (smith, 2009, 196). heavy snow damages manmade structures, crops, casualties, even between urban and rural ways of blocking.(briant. 69, 2005. ohara et al, 2009, 1611). various definitions have been offered for heavy snow, those are c...

the concentrations of some heavy metals in sediment from the sinop coasts of the black sea were measured to monitor metal pollution in 2013. the distribution of the heavy metals in sediments of the black sea shows a variable pattern. the objectives of the present study were to elucidate the distribution heavy metals such as cu, pb, zn, ni, mn, fe, as, cd, cr, hg and co in sediment from sinop co...

The concentrations of some heavy metals in sediment from the Sinop coasts of the Black Sea were measured to monitor metal pollution in 2013. The distribution of the heavy metals in sediments of the Black Sea shows a variable pattern. The objectives of the present study were to elucidate the distribution heavy metals such as Cu, Pb, Zn, Ni, Mn, Fe, As, Cd, Cr, Hg and Co in sediment from Sinop co...